This book presents the most comprehensive summary of long-term atmospheric research at the only World Meteorological Organization (WMO)/Global Atmosphere Watch (GAW) global station in the Mediterranean basin. Includes tables and plots reporting on the basic climatology of climate-altering/pollutant molecules, providing a reference for the Mediterranean basin background in the lower troposphere. Describes the current state of knowledge on long- and short-term atmospheric composition variability in the central Mediterranean basin